METHOD AND DEVICE OF ELECTRICAL POWER

• US 20120032651A1
• Filed: 10/10/2011
• Published: 02/09/2012
• Est. Priority Date: 05/24/2010
• Status: Active Grant

• Current Assignee: Huawei Digital Power Technologies Company Limited (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Torrico-Bascopé, Grover Victor
• Granted Patent: US 8,395,913 B2
• Time in Patent Office: Days
• US Class Current: 323/209
• CPC Class Codes: H02M 1/0064 Magnetic structures combining different functions, e.g. storage, filtering or transformation
• CPC Class Codes: H02M 1/4216 operating from a three-phase input voltage H02M1/4233 takes precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A power factor correction of three-phase boost-type conversion is disclosed. Embodiments comprising multi-leg autotransformers are disclosed, e.g. comprising 3-phase low-pass filtering impedances such as capacitors between an input of a converter and a midpoint of the output.

Claims

1. A method of power factor correction of a 3-phase power converter comprising:

connecting each phase to a midpoint across an autotransformer.

2. The method according to claim 1, wherein a three-phase input of the power converter is connected to a midpoint of the output of the power converter across a low-pass filtering impedance.

3. The method according to claim 1, wherein each phase of a three-phase input of the power converter is connected to a midpoint of the output of the power converter across a capacitor.

4. The method according to claim 1, wherein each phase is connected to a mid-point over controllable bi-directional switch.

5. The method according to claim 1, wherein the autotransformer comprises a plurality of transformer legs.

6. The method according to claim 5, wherein each transformer leg is connected to the midpoint at a connection, the connection comprising two diodes.

7. The method according to claim 6, wherein each transformer leg is connected to the midpoint through a plurality of controllable bi-directional switches.

8. The method according to claim 6, wherein the respective diodes are connected to the positive and negative side of the output of the power converter.

9. The method according to claim 7, wherein the plurality of controllable bi-directional switches, each connected to the leg of the autotransformer, the autotransformer and the diodes form a multi-state switching cell.

10. The method according to claim 9, wherein there is one multi-state switching cell for each phase providing 7 pairs of operational modes.

11. The method according to claim 7, wherein the plurality of controllable bi-directional switches, each connected to the leg of the autotransformer, the autotransformer and the diodes form a five-state switching cell.

12. The method according to claim 1, wherein the midpoint is the midpoint of a positive principal voltage and a negative principal voltage, the principal voltage being greater than the line voltage.

13. The method according to claim 12, wherein output voltage corresponds to a peak voltage value that is greater than the peak value of the principal line voltage of the input.

14. A device comprising:

an autotransformer inter-connecting each phase to a midpoint, wherein the device corrects power factor of a 3-phase power converter.

15. The device according to claim 14, comprising a low-pass filtering impedance connecting a three-phase input of the device to a midpoint of the output of the device.

16. The device according to claim 14, comprising a capacitor connecting each phase of a three-phase input of the power converter to a midpoint of the output of the power converter.

17. The device according to claim 14, comprising bi-directional switches connecting each phase to the mid-point.

18. The device according to claim 14, comprising an autotransformer comprising two transformer legs.

19. The device according to claim 18, comprising two diodes connecting each transformer leg to the mid-point.

20. The device according to claim 19, comprising a plurality of controllable bi-directional switches connecting as closed each transformer leg to the midpoint.

21. The device according to claim 19, wherein the respective diodes are connected to the positive and negative side of the output of the power converter.

22. The device according to claim 20, wherein the plurality of controllable bi-directional switches are each connected to a leg of the autotransformer, the autotransformer and the diodes forming a multi-state switching cell.

23. The device according to claim 22, comprising one multi-state switching cell for each phase providing 7 pairs of operational modes.

24. The device according to claim 20, wherein the plurality of controllable bi-directional switches are each connected to a leg of the autotransformer, the autotransformer and the diodes forming a five-state switching cell.

25. The device according to claim 14, wherein the midpoint is the mid-point of a positive principal voltage and a negative principal voltage, the principal voltage being greater than the line voltage.